26th August 2024

An 84-year-old man presents to your clinic with pain and weakness in his left arm

An 84-year-old man presents to your clinic with pain and weakness in his left arm which has developed over the past year. On examination, he has weakness of elbow, wrist, and finger extension but normal flexion. His triceps reflex is diminished but all other reflexes are normal. He has pain and abnormal sensation over the dorsum of his forearm and his middle finger. What’s the most likely location of his lesion?

Select the SINGLE most appropriate option from the list below. Select ONE option only.